Add settings page for managing forecasting API key and URL via UI

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/node_modules/es-abstract/2020/IsValidIntegerIndex.js

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+'use strict';
+
+var $TypeError = require('es-errors/type');
+
+var IsInteger = require('./IsInteger');
+
+var isNegativeZero = require('math-intrinsics/isNegativeZero');
+
+var isTypedArray = require('is-typed-array');
+var typedArrayBuffer = require('typed-array-buffer');
+
+// https://262.ecma-international.org/11.0/#sec-isvalidintegerindex
+
+module.exports = function IsValidIntegerIndex(O, index) {
+	if (!isTypedArray) {
+		throw new $TypeError('Assertion failed: `O` must be a Typed Array');
+	}
+
+	typedArrayBuffer(O); // step 1
+
+	if (typeof index !== 'number') {
+		throw new $TypeError('Assertion failed: Type(index) is not Number'); // step 2
+	}
+
+	if (!IsInteger(index)) { return false; } // step 3
+
+	if (isNegativeZero(index)) { return false; } // step 4
+
+	if (index < 0 || index >= O.length) { return false; } // step 5
+
+	return true; // step 6
+};